Leather-scratching machine



LEATHER SCRATCHING MACHINE Filed M y 14. 1928 2 Sheets-Sheet 1 Zrzuarz Z0)- MM W467 Dec. 24, 1929. w. $.GRIFFITH LEATHER SCRATCHING MACHINE Filed May 14, 1928 2 Sheets-Sheet 2 fig 5.

Patented Dec. 24, 19.29

UN i so smres WINFRED S. GRIFFITH, OF WORCESTER, MASSACHUSETTS, ASSIGNOR T 'GBATON '80 KNIGHT COllIPANY, OF \VORCESTEE, IVIASSAGEZUSE'ITS, A CORPORATION-OF IvIASSA- CHUSETTS LEATHER-S63E11 CHINE: MACHIN E Application filed May 14, 1928. Serial No. 277,752.

This invention relates to a machine particularly designed for preparing the flesh .side of a belt-priorto a cementing or gluing operation. Before cementing together he two-parts of a double leather belt, it is essential that all fleshy parts of the leather be removed and thattheinner surface of the belt be brushed or scratched to give it a uniform -and slightly roughened surface.

These operations have been-heretofore commonly performed by scraping and carding manually,.and'it-isthe, general object of my invention .to provide mechanical means by which equivalent operations may be effec -tively performed at a substantial saving of time and material. My present invention relates specifically to a machine for scratching or raising the fieshing material from the flesh side of the belt so that it may be con veniently removed at a subsequent operation.

7 More particularly, 1 providea roughened scratching cylinder rotating at relatively high speed and Iprovide especially designed means for pressing the flesh side of a leather belt against the rotating cylinder with a su stantially uniform pressure throughout its widtl1,-regardless of variations in the thickness of the leather.

My invention further relates to arrangements and combinations 'of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown I in the drawings in which :Fig. 1 is a plan view of my improved scratching machine;

Fig. 2 is an end view of certain parts, look ring in the direction of the arrow 2 in Fig. 1;

Fig. 3 is a sectional end elevation, taken r along the line 33 in Fig. 1, and

Fig. 4 is a detail side elevation, looking in thedirection of the arrow 4 in Fig. 3.

Referrin to the drawln in improved b p scratching machlne comprises a frame 10 (Fig. 3) having tables or supports 11 and 12mounted thereon. A lower feed roll 13 is-rotatable in fixed bearings 1n the frame 10 and is provided with a spiral gear 14 engaged ,by-a corresponding spiral gear 1 5 (r 1g. 2) on a cross shaft 16, mounted in bearings at the end of the frame 10. A worm gear 17 is secured to the cross shaft '16 and is engaged by a worm 18 on a roll shaft 19 rotatable in bearings 20 (Fig. 1) supported by the frame 10 and having a driving pulley secured thereto and rotated by a belt .23 from any suitable source of power.

A. scratching roll 24 (Fig. 3) is mounted on the shaft 19 and is provided witha roughened surface, which may preferablybe formed by securing a covering of cardclothing 25 to the periphery thereof. The roll 13 is commonly of wood andis preferably pro-.

boxes 31. The roll 30 is preferably provided with a relatively thick and soft covering 37 of rubber which will yield to the inequalities of the'belt as it passes thereunder.

A series of presser fingers 40 are pivoted on a cross rod 41, supported in brackets 42. A cross bar 43 connects the brackets at opposite sides of the machine. Bolts 44 are secured to the brackets 42 and extend through plates 45 fixed to fixed portions ofthe'feed roll bearing frames.

Heavy coil springs 46 force the presser fingers 4O and'their supporting structure to the right. as viewed in Fig. 3, and such movement is limited by wing nuts 47 on the bolts '44. By'turning the nuts '47, the presser fingers may be positioned in desired relation to the scratching roll 24.

Each presser finger has a belt contacting element-48insertedinitslower face, preferably formed from a small disc of hardened steel forced into an opening in the lower edge of the finger andpositioned to engage the belt directly above the scratching roll 24. Each finger 40 also has an upward extension 50, having an opening therein through which loosely extends a bolt or screw 51 threaded in the cross bar 413.

A coil spring 52 surrounds each screw 51 and provides yielding resistance to upward movement of each separate finger. The vertical position of the contact faces of the fingers and also the spring tension thereon may be adjusted by turning the screws 51.

Having thus described my invention, the method of operation is as follows:

A belt B is fed into the machine over the table 11 and is engaged between the surfaces of the feed rolls 13 and 30, by which it is slowly advanced to the brushing roll 24; and presser fingers 40. The card-clothing25 rotates at very much greater speed than the travel of the belt but in the same direction, and acts to tear up the soft fleshy material remaining on the under side of the belt. The fingers 40 are self-adjusting and apply substantially uniform pressure of the belt throughout its width, regardless of variations in the thickness of the leather.

It is frequently desirable to run the belt through the scratching machine two or more times before skiving OK the projecting fleshy material and this is readily accomplished by looping the end of the belt over the machine and again inserting it between the feed rolls,

the rolls being of such length that the belt may pass several times through the machine simultaneously if desired.

For guiding the belt over the table 11 to the feed'rolls, I provide a plurality of guidepins 60, which may be inserted in selected holes 61 spaced across the table 11. By inserting several such guide-pins, the belt may be passed several times through the machine in succession and the different loops of the belt will be kept separate and will be prevented from interference with each other.

When the belt leaves the machine, the fleshy material extends loosely from the flesh side of the belt and may thereafter be easily removed therefrom by a skiving or shaving opration.

Having thus described my invention and the advantages thereof, 1 do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is 1. A belt scratching machine comprising feeding mechanism, a scratching cylinder provided with a great number of stiff outwardly projecting teeth of substantially uniform length, and means to press against said scratching cylinder at substantially uniform pressure the flesh side of all portions of a belt fed through said machine, said pressure being substantially independent of minor variations in belt thickness.

2. A belt scratching machine comprising feeding mechanism, a scratching cylinder provided with a great number of stiff outwardly projecting teeth of substantially uniform length, and a plurality of independently operating pressure devices effective to press against said cylinder at substantially uniform pressure all portions of a belt fed through said machine, said pressure being substantially independent of minor variations in belt thickness.

3. A belt scratching machine comprising feeding mechanism, a scratching cylinder provided with a great number of stiff outwardly projecting teeth of substantially uniform length, and a plurality of presser members each yieldingly and independently engaging a belt fed through said machine and effective to press all portions thereof against the scratching cylinder at substantially uniform pressure, said pressure being substantially independent of minor variations in belt thickness.

4:. A belt scratching machine comprising feeding mechanism, a scratching cylinder provided with a great number of stiff outwardly projecting teeth of substantially uniform length, a plurality of presser fingers, and a separate spring for each finger effective to press each finger independently of the other fingers against a belt fed through said machine, said fingers being collectively effective to press all portions of said belt against said scratching cylinder at substantially uniform pressure.

5. A belt scratching machine comprising feeding mechanism, a scratching cylinder provided with a great number of stiff outwardly projecting teeth of substantially uniform length, a plurality of presser fingers mounted on fixed pivots, and a separate spring for each finger efiective to swing each finger on its pivot independently of the other fingers against a belt fed through said machine, said fingers being collectively effective to press all portions of said belt against said scratching cylinder at substantially uniform pressure.

6. In a belt scratching machine, a pair of feed rolls, a scratching cylinder covered with car-d clothing and rotatable in the direction of belt travel, a support for the belt as it approaches the feed rolls, and means to guide the belt in a selected path of approach.

7. In a belt scratching machine, a pair of feed rolls, a scratching cylinder covered with card clothing and rotatable in the direction of belt travel, a support for the belt as it approaches the feed rolls, and means to guide the belt in a selected path of approach, said meians being adjustable axially of said feed rol s.

8. In a belt scratching machine, a pair of feed rolls, a scratching cylinder covered with card clothing and rotatable in the direction of belt travel, a support for the belt as it approaches the feed rolls, and means to guide WINFRED S. GRIFFITH. 

